Generally, hydrosilylation involving reactions between silyl hydride and unsaturated organic groups is used not only for various addition-cured products such as sealants, adhesives, and silicon-based coating products, but also is the basic principle in the synthesis process for producing commercial silicon products such as silicon surfactants, silicone oil, and silane. Up until now, in general, hydrosilylation has been accelerated by noble metal catalysts such as platinum or rhodium metal complexes.
For example, platinum-based hydrosilylation catalysts include Ashby's catalyst, Lamoreaux's catalyst, Karstedt's catalyst, Speier's catalyst, etc. However, although these noble metal complex catalysts have been widely recognized as catalysts for hydrosilylation, they have a few disadvantages.
The Korean Laid-Open Patent Publication No. 10-2014-0041578 (Patent Document 1) discloses a hydrosilylation catalyst including a platinum-ligand complex, a hydrosilylation curable composition including an aliphatic unsaturated compound, and the preparation method and the use method thereof. When these expensive noble metal catalysts are used, they account for a significant part of the cost for silicon formulations. Recently, global demand for precious metals including platinum has increased, and as a result, effective and inexpensive replacement catalysts are needed.
As an alternative to precious metals, recently, several iron complexes have attracted attention for use as hydrosilylation catalysts. For example, technical journal papers have disclosed that Fe(CO)5 catalyzes hydrosilylation at high temperatures (C. Randolph, M. S. Wrighton, J. Am. Chem. Soc. 108(1986)3366). However, there remains a problem in that undesirable side products such as unsaturated silyl olefin, which is a product of dehydrogenative silylation, are also produced.
In addition, the Korean Laid-Open Patent Publication No. 10-2014-0035318 (Patent Document 2) discloses metal-catalyst mono hydrosilylation of poly unsaturated compounds by selectively using non-noble metal pyridine and terpyridine complexes as catalysts for hydrosilylation.
However, these non-noble metal-based complex catalysts still have problems in that it is difficult to remove heavy metals remaining in the resin because these catalysts contain heavy metals.
Therefore, a method for preparing a hydrosilylation catalyst and a silicon polymer, which improve economic feasibility and do not require removal of residual heavy metals while maintaining a high yield and reactivity in place of conventional expensive noble metal catalysts, is needed.
[Patent Document 1] Korean Laid-Open Patent Publication No. 10-2014-0041578
[Patent Document 2] Korean Laid-Open Patent Publication No. 10-2014-0035318